China’s heightened interest in saving energy — a response to electricity shortages and blackouts this year as well as longer-term security worries about dependence on energy imports — comes as the country’s construction industry continues to barrel ahead at a breathtaking pace. Last year, China consumed eight times as much cement as the world’s second-largest consumer, India, and it now leads the world in consumption of steel and other industrial materials by wide margins.

With 13 million to 21 million rural people in China migrating to cities each year — a number comparable to the 18.9 million people in metropolitan New York — the real estate industry has been putting up office towers and apartment buildings at a brisk pace but often with little regard for energy efficiency.

Chinese estimates show that the country’s commercial office buildings use 10 to 20 percent less electricity per square meter than comparable Western buildings. But the savings tend to come not from better designs but from thermostats set as high as 26 degrees Celsius (79 Fahrenheit) in summer and as low as 18 degrees (64 Fahrenheit) in winter.

Senior executives in the glass manufacturing and other material industries said that Chinese construction companies had long chosen low-cost, less insulated materials because buildings in China tended to change hands so frequently that owners seldom looked at long-term paybacks from electricity savings.